The invention concerns an angle gear for a vehicle steering mechanism with bevel gears which can be axially displaced in a housing and whose axes form an angle with each other.
It is frequently necessary, particularly in vehicles with controlled axles arranged essentially below the passenger compartment, e.g., in small goods carriers and buses designed as front wheel drive vehicles, to insert an angle gear into the steering mechanism. This angle gear transmits the steering movement from the steering shaft, which suitably extends towards the front and bottom of the vehicle with an inclination, to the shaft leading to the steering mechanism arranged on the controlled axle.
In order to ensure the quality of such angle gears, it is necessary to adjust the bevel gear pairs of these angle gears that mesh with each other, with the smallest possible rotation backlash. On the other hand, such rotation backlash must not be eliminated in its entirety because in such a case there would arise the danger of the tooth flanks squeezing each other during rotation of the gears. Such an adjustment of the rotation backlash of the bevel gears to the smallest possible values may be obtained by the insertion of correspondingly dimensioned spacers or thrust washers between the housing of the angle gear and the bevel gears. As a result, the bevel gear shafts must be axially adjustable in opposition to the forces that occur during a steering operation, i.e. in the direction towards the intersection of the axes of the two shafts. Such axial adjustability of the bevel gear shafts, however, is disadvantageous in that in case of a load on the bevel gears in opposition to the forces generated during steering, e.g. due to axial stress on the steering shaft or distortions of the vehicle frame, the bevel gears are still axially stressed in the direction towards elimination of all rotation backlash, with all the detrimental consequences resulting therefrom.